1. Field of the Invention
The present invention relates generally to a method for automatic wireless connection between a portable terminal and a digital device, and more particularly, to a system and method for automatic wireless connection between a portable terminal and a digital device, enabling a user to conveniently access a Wireless Local Area Network (WLAN).
2. Description of the Related Art
Compared with an existing wired Local Area Network (LAN) that communicates data to and from accessing devices through connecting cables, WLAN wirelessly communicates data to and from the accessing devices using Radio Frequency (RF) signals. WLAN communication may be classified into an infrastructure mode and an Ad-hoc mode. In the infrastructure mode, the WLAN communicates with a client through an Access Point (AP), and in the Ad-hoc mode, the WLAN communicates directly with clients.
Generally, because many digital devices (e.g., a portable terminal, a Personal Computer (PC), a camera, and a printer) do not support the AP function, they communicate with each other using the Ad-hoc mode. In order to access WLAN using the Ad-hoc mode, the digital devices use a Service Set Identifier (SSID) and a security key for authentication and encryption, and set an Internet Protocol (IP) address for IP communication. Because most new digital devices have a WLAN interface, a user connects these digital devices using the Ad-hoc mode of the WLAN. However, for Ad-hoc communication with WLAN, a WLAN connection process and an IP address setting process for IP communication are performed.
In the WLAN connection process, specifically, for an Ad-hoc connection, an SSID setting process and a security setting process are performed. In the WLAN SSID setting process, because WLAN is used by several devices to communicate with each other by sharing a particular physical frequency band based on Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA), SSID is used to distinguish the network in the physical channel. That is, SSID is an identifier used to configure a logical WLAN network in a physical channel. Accordingly, communication is possible between nodes, e.g., APs or clients, which have the same SSIDs. Therefore, in order to use this method, each node should have the same SSID information in order to communicate with certain nodes using WLAN.
In the WLAN security setting process, compared with the existing wired LAN, WLAN is vulnerable to security, because it wirelessly communicates data using a particular frequency. Therefore, unlike the wired LAN, WLAN basically needs an authentication and encryption scheme. The authentication process permits an authorized node or user to access WLAN, and is used to encrypt and communicate data through a scheme predetermined between transmission and reception nodes, such that other nodes may not access the data.
In the Ad-hoc mode, open authentication and shared authentication are available, and authentication and encryption are achieved by a Wired Equivalent Privacy (WEP) scheme. That is, in order to communicate with certain nodes using WLAN, each node uses the same authentication and encryption scheme, and uses a WEP Key value in the Ad-hoc mode.
In the IP address setting process, because WLAN corresponds to a link layer (or Layer 2) in an Open System Interconnection (OSI) 7 Layer, an IP address is set for a WLAN interface for IP communication that is a network layer or actual Layer 3. Generally, for IP communication, nodes joining one broadcast domain should have IP addresses belonging to the same subnet, and the IP addresses should be unique in the broadcast domain. The nodes may each have several LAN cards or interfaces and several IP addresses, and each IP address should belong to a different subnet.
FIG. 1 is a flowchart illustrating a conventional setting and connection procedure for WLAN connection.
Referring to FIG. 1, in step 110, a user activates a WLAN interface by setting the WLAN to the Ad-hoc mode. Thereafter, the user inputs an SSID of the WLAN to set the SSID of the WLAN in step 120. In step 130, the user inputs a security key of the WLAN, in order to set the security key of WLAN. In step 140, the user inputs and sets an IP address of the WLAN. Consequently, Ad-hoc communication connection is achieved in step 145. However, as described above, for the WLAN connection, the user inputs information for the WLAN settings and connection in each step.
Additionally, checking and activating a state of the WLAN is possible through WLAN management software of the operating system. That is, the WLAN is turned On/Off using the software. Accordingly, the user should know how to use the WLAN management software, and should have knowledge concerning the state of the WLAN interface.
In addition, the user sets the WLAN to the Ad-hoc mode and sets the SSID and the WEP Key through the WLAN management software. Generally, in order to set the WLAN to the Ad-hoc mode and input the SSID and WEP Keys, the user reselects an SSID and WEP Key setting menu and sets them in an input window, after running the WLAN management software. However, as described above, this is not the easiest process as the user should have knowledge concerning the WLAN and know how to use the WLAN management software.
Commonly, a node accessing the Internet is assigned an IP address from a Dynamic Host Configuration Protocol (DHCP) server using DHCP. That is, the user uses the assigned IP address without directly setting the IP address. However, in an Ad-hoc WLAN connection, the user directly sets an IP address for the WLAN interface without using the DHCP scheme. Therefore, in order to set an IP address, the user should have knowledge of the IP address and know how to use IP address management software.
For the WLAN connection setting, the user should know how to use the WLAN and IP address management software, and have knowledge of WLAN and IP address. The use of WLAN may be complicated for the users who have no knowledge of WLAN and IP address or are unfamiliar with use of the WLAN and IP address management software. Further, this information is not the information that the user should know in order to perform communication using an application, as the main purpose of the user is to use the application after WLAN connection. Accordingly, it is inefficient and inconvenient for the user to input the setup and connection information one by one, and have to continuously change the settings due to frequent movement.
As described above, the user can use most of the applications using WLAN after setting an SSID, a security key and an IP address according to a predetermined procedure. However, the SSID, the security key and the IP address are not directly used in these applications, after being set. Therefore, it is inefficient for the user to input information one by one, and this setting procedure is a very complicated and inconvenient to the user, who is unfamiliar with use of WLAN and should continuously change settings due to his frequent movement.